In addition to the release notes below, you can also track known issues on the
issue tracker.

July 10, 2018

App Engine is now available in the us-west2 region (Los Angeles).

May 4, 2018

Applications in the App Engine flexible environment currently use a Debian 8
"Jessie" operating system. The Debian 8 "Jessie" OS will lose full support from
the Debian maintainers in June 2018. In advance of this change, Google will
migrate customers to an Ubuntu-based OS starting on May 30, 2018. To update your
application to the Ubuntu 16.04 OS, re-deploy your application after May 30,
2018.

October 31, 2017

October 11, 2017

October 2, 2017

For the App Engine flexible environment, all responses are now compressed with
gzip by default once you redeploy your app. No changes need to be made to
your app.yaml file.

September 26, 2017

For the App Engine flexible environment, billing increments for instances are
reduced from per-minute increments to per-second increments. Additionally, the
minimum usage cost for instance resources is reduced from 10 minutes to 1
minute.

Legacy health checks will no longer be available after September 30th, 2018.

September 13, 2017

You can now use managed certificates to add SSL to your custom
domain. Once you map your custom domain to your application, App Engine
provisions an SSL certificate automatically and handles renewing the
certificate before it expires and revoking it if you remove the custom domain.
Managed certificates are in beta. For more information, see
Securing Custom Domains with SSL.

September 5, 2017

App Engine is now available in the southamerica-east1 region (São Paulo,
Brazil).

August 30, 2017

The Ruby runtime is now backed by an improved build pipeline with a number
of fixes and enhancements. In particular, build tasks, such as Rails asset
precompilation, now have access to the application's environment variables
and Cloud SQL databases, if any. Update the gcloud sdk to version 169.0.0 or
later to use this new build pipeline.

August 23, 2017

August 1, 2017

App Engine is now available in the europe-west3 region (Frankfurt, Germany).

July 18, 2017

App Engine is now available in the australia-southeast1 region
(Sydney, Australia).

July 12, 2017

You can now use updated health checks, which allow you to use separate checks
to confirm that your instance is running and ready to serve content. You must
enable updated health checks, which are currently in Beta. For more information,
see Health checks.

If you use updated health checks, deployments will fail if your application
does not reach a ready state.

May 9, 2017

App Engine is now available in the us-east4 region (North Virginia).

April 11, 2017

Added information about
upgrading from the App Engine Task Queue API in the compat runtimes to using
Cloud Tasks (alpha) in the flexible environment and added information for how
to verify requests from the Task Queue API.

December 6th, 2016

New applications that have not been deployed in the flexible environment must
specify env: true in the app.yaml file instead of vm:true. Applications
that were previously deployed can continue to use vm:true but will need to
switch to env:true in the future. For more details, see
upgrade guide.

The Ruby runtime now runs Ruby 2.3.3 by default. If your application requires
a different version of Ruby, include a .ruby-version file
at the root of your application directory.

November 15th, 2016

There is a new release of the App Engine flexible environment. To choose this
environment, use env:flex instead of vm:true in your app.yaml
configuration file. You can learn more about the details of this release by
visiting the
upgrade guide.

There are two mechanisms for building the container image remotely. The
default behavior is to build the container on a transient Compute Engine
Virtual Machine which has Docker installed. Alternatively, you can use the
Cloud Build service, which is in Beta. To
use the Cloud Build service, follow these steps:

Use the command gcloud config set app/use_cloud_build True. This will
cause all invocations of gcloud preview app deploy to use the
service. To return to the default behavior, use the command
gcloud config set app/use_cloud_build False.